Abrasive fluid or water jet cutting has been used for some time in applications limited to cutting material where damage to the surrounding substrate from heat, vibration, and other products of conventional cutting methods cannot be tolerated.
For example, Yie, U.S. Pat. No. 4,478,368, discloses a slurry water jet process for cutting steel and concrete. Further, I. M. Hutchings, Mechanisms of the Erosion of Metals by Solid Particles, Erosion: Prevention and Useful Applications, ASTM STP 664, W. F. Adler Ed., American Society For Testing Materials, 1979 pp. 59-76, discloses experiments that illustrate the behavior of spherical and angular particles on oblique impact with a metal surface. R. H. Hollinger et al, Precision Cutting with a Low Pressure, Coherent Abrasive Suspension Jet, 5th American Water Jet Conference, pp. 245-252, Aug. 29-31, 1989: Toronto, Canada, disclose conventional water/abrasive jet cutting using entrained abrasive particles in a water jet.
H. Y. Li et al, Investigation of Forces Exerted by an Abrasive Water Jet on a Workpiece, 5th American Water Jet Conference, pp. 69-77, Aug. 29-31, 1989: Toronto, Canada, disclose the development of practical procedures for the measurement of forces exerted on a workpiece in the impingement zone. K. F. Neusen et al, Impact of Liquid Jets at Velocities Approaching Liquid Sound Speed, Journal of Florida Engineering, Transactions of the ASME, pp. 198-202, Sep. 1974, disclose experiments to obtain information concerning the action of high velocity liquid jets impacting at velocities that erode the target surface.
M. Hashish, Steel Cutting with Abrasive Waterjets, Sixth Intl. Symposium on Jet Cutting Technology, April 6-8, 1982, pp. 465-487, discloses steel cutting with high velocity abrasive waterjets. Also, M. Hashish, On the Modeling of Abrasive-Waterjet Cutting, Seventh Intl. Symposium on Jet Cutting Technology, Jun. 26-28, 1984, pp. 249-265, discloses an effort to model the abrasive-waterjet cutting processes by visualization of the cutting interface and an analysis of the erosion process by abrasive-waterjets. Also, by Hashish, Pressure Effects in Abrasive-Waterjet Machining, Journal of Engineering Materials and Technology, July 1989, Vol. III, pp. 221-228, discloses abrasive-waterjets that are formed by mixing high pressure waterjets with abrasive particles and mixing typical inlet/discharge ratios of 50 to 100. Krasnoff, U.S. Pat. No. 4,723,387, discloses both a batch operation and a continuous operation for supplying pressured liquid and a pressured slurry to an abrasive-jet cutting nozzle.
Drawbacks of fluid or water abrasive jet cutting has always been the slowness of the jets cutting speed on materials such as metals as well as other thick or dense materials. Many methods of overcoming this problem have been tried. Current attempts at increasing cutting speed include increasing the pressure of the waterjet, using a larger orifice, using a sharper or harder form of abrasive, and achieving a more coherent stream. However, the more viscous the fluid layer surrounding each particle, the more energy required to penetrate the target material. This reduces the amount of energy available to cut the target material.
As a result, a need exists for a fluid jet cutting composition and method which penetrates not only solution existing on the surface of the substrate to be cut, but also penetrates the surface itself at a higher velocity than now presently available through current methods.